US Navy’s Autonomous Robotic Ship

Diesel-electric submarines are cheap, incredibly quiet, easily produced, and pose a great threat to US Naval supremacy. Their travel range is limited, as is their speed, however strategically placed they could deny the US Navy access to coastal areas and disrupt seaborne trade.

“Picking up the quiet hum of a battery-powered, diesel-electric submarine in busy coastal waters is like trying to identify the sound of a single car engine in the din of a major city,” Rear Admiral Frank Drennan, commander of the Naval Mine and Anti-Submarine Warfare Command, warned in March 2015.

To counter advancements in next generation submarine technology, the US Defence Advanced Research Projects Agency (DARPA) is developing an autonomous robotic sea vessel for surveillance purposes. The Anti-Submarine Warfare Continuous Trail Unmanned Vessel (ACTUV) is designed to operate for 60 to 90 days straight, surveilling large swathes of nautical territory for hostile submarines.

“Instead of chasing down these submarines and trying to keep track of them with expensive nuclear powered-submarines, which is the way we do it now, we want to try and build this at significantly reduced cost. It will be able to transit by itself across thousands of kilometers of ocean and it can deploy for months at a time. It can go out, find a diesel-electric submarine and just ping on it,” said DARPA project manager Ellison Urban.

The ACTUV has now been fitted with Raytheon’s Modular Scalable Sonar System (MS3). It will serve as ACTUV’s primary search and detection sonar.

Construction of Sea Hunter, the first full-scale prototype, is 90 percent complete. It is set to begin testing in January 2016. The 40 meters long vessel weighs 140 tons, and has an estimated operational cost of $15,000-$20,000 per days, a fraction of the $700,000 per day for a US Navy destroyer with a similar mission profile.